Generic construction vehicles, more particularly, ground milling machines such as road milling machines, recyclers, stabilizers, or surface miners, are frequently used in road and path construction. They comprise a machine frame, an operator's platform, a plurality of crawler tracks, and a drive engine, usually of the Diesel type. The key element of such a ground milling machine is a milling drum mounted for rotation within a milling drum box. This usually consists of a hollow cylinder, comprising a large number of chiseling devices on its outer cylindrical surface. During operation of the ground milling machine, the rotation of the milling drum causes this chiseling equipment to be driven into the ground so as to remove the ground material. The milled material is generally conveyed by a discharge conveyor, either in the direction of advance or contrary thereto, for transfer to a transport vehicle and dispatched. The rear surface of the milling drum box, as regarded in the direction of advance, is frequently constructed as a vertically adjustable stripping device comprising a stripping plate. Ground milling machines comprising such stripping devices are disclosed, for example, in DE 102012012607.7 and DE 102012018918.4.
During operation, the stripping plate of the stripping device is guided with its bottom plate edge either directly scraping the surface of the milled bed, or in a raised position just above it. It is the purpose of the stripping device to leave a clean milled bed behind the ground milling machine, leaving either no milled material or only a desired amount of milled material in the milled bed, as can be achieved by adjusting the height of the stripping device, which also makes it possible to adapt the latter to various milling depths. In particular, when no milled material is to remain in the milled bed and the stripping plate is thus in direct contact with the milled bed, particularly those regions of the stripping plate that touch the milled bed and the flanks of the milled groove will be subjected to a high degree of stress, resulting in rapid wear thereof. For this reason, the stripping device is usually equipped, in addition to the stripping plate, with an interchangeable stripping bar, which is disposed on the edges oriented toward the milled bed, more particularly, the bottom plate edge, of the stripping plate.
During operation, the stripping bar is in direct scraping contact with the milled bed and the flanks of the milled groove, so that the bottom plate edge of the stripping plate is not in direct contact with the milled bed and is thus protected from wear. The stripping bars are usually made of metal, for example, steel, and are equipped with carbide wear protection and made up of a number of individual stripping elements. The use of a number of individual elements makes it possible to replace only those individual elements which suffer greater wear due, for example, to cornering maneuvers or one-sided milling of edges, and thus to save costs. There are usually different stripping elements provided for different positions along the edge of the stripping plate, since it is known, on the one hand, which regions normally wear down more rapidly, and allowance is made, on the other hand, for optimization of the stripping elements for operation at their specific position (e.g., in the transition regions between horizontal and vertical edges).
The stripping elements are usually mounted onto the stripping plate via a suitable mounting device. Said mounting device may, for example, comprise through holes, screws or mounting bolts and fastening nuts. To this end, it is necessary to select the stripping element that is designated for the respective position on the stripping plate and to arrange this on the stripping plate in such a way that it can be mounted thereto via the mounting device, for example, by aligning the screw-threaded holes of the mounting device so as to lie coaxially against each other, so that a mounting screw can be inserted. For guidance, the assembler can only refer to the length of the different stripping elements and partially also elements of the mounting device such as the distance between the usually two screw-threaded holes required for the bolted connection. No other aid is provided to indicate where which stripping element is to be placed on the stripping plate. Additionally, depending on the specific design of the mounting device, slippage of the stripping elements might occur prior to or during the bolting operation, with the result that the screw threaded holes lose coaxial alignment, which would necessitate moving the stripping element back and forth until the desired position has been re-established. This can lead to the assembler having to reposition the individual stripping elements a number of times before the screw threaded holes regain coaxial alignment and assembly can be completed. In addition, the mounting device, and, if present, in particular, the bolted connections of the mounting device are usually required to absorb all forces exerted on the stripping elements and to transfer these to the stripping plate. High shearing forces, in particular, can lead to failure of the screws, resulting in the stripping bar not being able to function properly.
It is thus an object of the present invention to simplify the assembly of stripping elements on a ground milling machine's stripping device, and at the same time to provide improved force transmission from the stripping elements to the stripping plate.